Brazilian jiu-jitsu (BJJ) is a martial art, combat sport, and a self defense system that focuses on grappling and especially ground fighting. BJJ was formed from early 20th century Kodokan Judo ground fighting (Ne-Waza) fundamentals that were taught to Carlos Gracie by master Mitsuyo Maeda. BJJ eventually came to be its own art through the experimentations, practices, and adaptation from the Judo knowledge of Carlos who then passed their knowledge on to his extended family.

BJJ promotes the concept that a smaller, weaker person can successfully defend against a bigger, stronger assailant by using leverage and proper technique, taking the fight to the ground – most notably by applying joint-locks and chokeholds to defeat the other person. BJJ training can be used for sport grappling tournaments (gi and no-gi) and mixed martial arts (MMA) competition or self-defense. Sparring(commonly referred to as "rolling") and live drilling play a major role in training, and a premium is placed on performance, especially in competition, in relation to progress and ascension through its ranking system.